Researchers from the University of Southern Denmark (SDU) and Aarhus University in Denmark have developed a new additive for the livestock sector that could drastically reduce emissions of various gases from manure while reducing odors by 50%.
According to the announcement from Aarhus, the additive consists of the two naturally occurring substances: fluoride and tannins, which are common in products such as toothpaste, tea and red wine.
The researchers have filed for a patent on the technology, which consists of mixing tannic acid with small amounts of fluoride, SDU announced. The plan is to eventually develop a granulate that farmers can add to the manure.
The results have been published in the scientific journal Environmental Science & Technology.
"Our laboratory experiments are designed to mimic emissions in piggeries and clearly show great potential in reducing ammonia evaporation, methane emissions and odors," said Aarhus department of engineering post-doctoral researcher Frederik Rask Dalby, who has been responsible for laboratory experiments testing the additive on pig slurry.
The researchers believe that their new invention will lead to agriculture reducing its climate and environmental impacts in an easy and efficient manner, so their research has also had strong focus on ensuring that a new technology is affordable, Aarhus said.
"It’s important to keep the costs of environmental technologies in agriculture at a realistic level. Otherwise, it’ll be too expensive for farmers to implement these technologies. We’re currently working on optimizing the dosage of tannins in the additive to keep the price down," said associate professor Anders Feilberg with the air quality engineering research group in the Aarhus department of engineering.
The new technology was developed under the project "Next Generation Manure Ammonia Reduction Technology" funded by Denmark's Green Development & Demonstration Program. The project is headed by professor Henrik Karring from SDU Chemical Engineering, who calls the new additive a three-in-one technology.
"Laboratory experiments with pig slurry have shown that we can reduce ammonia evaporation by up to 95% and reduce emissions of methane by up to 99%, depending on the amount of added tannins and fluoride. As a welcoming and surprising bonus, it turns out that the same technology reduces the smell of manure significantly, corresponding to a 50% reduction on the odor index. It’s a three-in-one technology that can reduce ammonia evaporation, methane emissions and odors," he said.
Last year, Karring received $1.05 million from the Ministry of Environment & Food of Denmark. The money will be used to further improve the technology with a special focus on reducing methane emissions and testing the technology in pig barns, SDU said.
Before discovering the combination of tannic acid and fluoride, the researchers tested around 70 different additives. In addition to perfecting the dosage, the researchers continue to test new additives that might boost the technology.
"We've actually found several substances that have an effect. We're looking further into this, so I don't want to reveal anything yet, but it looks promising,” he said.